/**
 * Created with IntelliJ IDEA.
 * Description:
 * User: 石方旭
 * Date: 2022-04-06
 * Time: 18:09
 */
class X{
    public X(){
        System.out.print("X");
    }
}
class Y extends X{
    public Y(){
       // System.out.print("Y");
    }
}
public class Z {
    public static void main(String[] args) {
        new Y();
        new X();
    }
}